Store two numbers inside one number

gistfile1.js

function singleNumberToXY(number, boardWidth) {
	var x = number % boardWidth
	var y = (number - x) / boardWidth
	return {
		x: x,
		y: y
	}
}

function test(number, width) {
	console.log("Number:", number, "Width: ", width, singleNumberToXY(number, width))
}

test(10,8)
test(12,3)
test(6,4)